1. Field of the Invention
The present invention is in the field of cellular radio frequency communication system antennas and in particular heat dissipation from them.
2. Related Art
Antennas for cellular radio frequency communication systems, for example cellular telephone antennas, are advantageously arranged in configurations having a length that substantially exceeds the width of the antenna. A typical antenna may be two meters long and 30 centimeters wide. These antennas are usually mounted so that their long axis is substantially vertical. They are most frequently mounted on a cell phone tower that is often as high as 200 feet.
The antennas contain electrical components including modular radios, power supplies and/or transformers, radio frequency emitters and other components. In operation, these components generate heat. This heat should be dissipated in order to keep the operating electrical components at an advantageous temperature for effective and durable operation.
The antennas usually have a radome on one side. The antennas are typically mounted with the radome outermost, and with a back surface of the antenna facing the tower, as well as other structure, antennas and equipment that may also be mounted on the tower.
Active cooling components such as fans are problematic to install high on antenna towers, and so it is desirable to dissipate heat from antennas by passive means. Preexisting designs mounted heat dissipating fins on the back of the antenna. However, these fins were vertically aligned along the length of the antenna. Air heated by the components in the lower portion of the antenna would rise along the fins. The upper portions of the fins receiving this pre-heated air could not transfer heat from the upper components of the antenna efficiently. Further complicating considerations include the presence of the antenna in the open air during normal operations and the orientation of the heat exchanging (back) surface of the antenna towards the tower structure and other equipment mounted there. Of course, economy and the fabrication of components remains a consideration.